Living Walls

Properly, these Spanish projects installations should probably be called "living walls" rather than vertical gardens. Vancouver landscape architect Randy Sharp explains in Azure:

Green walls come in two main varieties, ac­cord­ing to Vancouver landscape architect Randy Sharp. His firm, Sharp & Diamond, designed the Vancouver Aquarium's 50-square-metre green wall of polypropylene modules filled with wildflowers, ferns and ground covers. A leading expert on "vegetated building envelope systems," Sharp divides these installations into green facades, where a structure fastened to the wall provides a trellis for vines and climbers planted in the ground or in containers; and the newer living walls, where a modular grid of wall pan­els - complete with live plants, a conventional soil or layered-felt growing medium, an irrigation and nutrient-delivery system, and a support structure - is attached to the building.

Patrick Blanc, the botanist who popularized the living wall, calls it Le Mur Végétal, or Plant Wall. It is usually fed by hydroponics and often uses no soil at all.

Green Façades

As noted by Sharp above, green facades have their roots in the ground and do not require pumps or technology to keep them alive. Édouard François has built a number of these; see Visiting Architect Édouard François In Paris

Vertical Farms

Vertical Farms are, according to Dr Dickson Despommier, urban highrises devoted to producing food. He writes in an essay:

One vertical farm with an architectural footprint of one square city block and rising up to 30 stories (approximately 3 million square feet) could provide enough nutrition (2,000 calories/day/person) to comfortably accommodate the needs of 10,000 people employing technologies currently available.

All of these terms are pretty clear; the term "Vertical garden" is not, as gardens can be used either for ornamental, decorative purposes or for food production. Perhaps the term should be retired.

In his post New Vertical Garden Comes to Spain's San Vicente , Alex wrote "Vertical gardens are here to stay." Our editor in chief wondered if there was a contradiction here with our post yesterday Fix Our Horizontal Farms Before We Go Vertical, where